Exercise and substance abuse

Impact of exercise on drug cravings: mediating role of cardiorespiratory fitness and inhibitory control

Background

Contemporary research has consistently demonstrated a link between physical exercise, inhibition, and drug cravings, with several hypotheses proposed to explain how exercise enhances inhibition. However, few studies have explored the mechanisms underlying this effect. This study investigates the pivotal role of cardiorespiratory fitness in mediating the impact of physical exercise on inhibition and drug cravings.

Methods

In this study, the researchers selected participants who had completed physical detoxification in China's compulsory isolation drug rehabilitation centers. Moreover, we conducted surveys and assessed cardiorespiratory fitness using tools such as the Physical Exercise Rating Scale, Inhibition Scale, Drug Craving Scale, and Queen College Step Test. Additionally, we employed exploratory and confirmatory factor analyses, correlation analysis, regression analysis, and structural equation model (SEM) to analyze the study's data.

Results and findings

The findings of this study reveal that physical exercise significantly reduces drug craving by improving cardiorespiratory fitness and enhancing inhibition. Furthermore, it showed that men had better physical exercise levels, cardiorespiratory fitness, and inhibition compared to women, while women exhibited higher psychological cravings. Besides, the study also highlighted that longer years of drug use were associated with lower physical exercise, reduced cardiorespiratory fitness, and weaker inhibition, leading to higher drug cravings. In addition, cardiorespiratory fitness and inhibition acted as mediators between physical exercise and drug craving, with the combination of both factors serving as a chain mediator in reducing cravings. These findings suggest that physical exercise, particularly through improving cardiorespiratory fitness, plays a key role in mitigating drug cravings and supporting rehabilitation efforts for drug dependence.

Impact of Exercise on Tramadol-Conditioned Place Preference

BACKGROUND

Tramadol (TRA) is an opioid that is used to manage moderate to severe pain. Long-term use of TRA can lead to the development of opioid use disorder.

OBJECTIVES

This study investigates the role of forced exercise in reducing TRA-seeking behavior.

METHODS

Adult male rats (240-260 g) were divided into five groups; the control group received vehicle injections, the TRA group received TRA (75 mg/kg, i.p) every other day for 8 days, and three TRA-exercise groups were forced to run on a treadmill (60 min/day, 5 days/week) for 2, 4, or 6 weeks prior to conditioning with TRA. A tramadol-conditioned place preference (CPP) procedure assessed TRA reinforcement, after which all rats were euthanized, tissue extracted, and mRNA expression for brain-derived neurotrophic factor (Bdnf) and interleukin 1 beta (Il-1β) determined in hippocampus (Hipp), prefrontal cortex (PFC), and nucleus accumbens (NAc).

RESULTS

TRA-seeking behavior was seen in the TRA group and the 6 weeks forced exercise group. By contrast, forced exercise for 2 or 4 weeks attenuated TRA-seeking behavior. This attenuation was associated with a significant increase in Bdnf mRNA expression in the Hipp and NAc, but not the PFC. Additionally, the TRA-induced elevations in Il-1β mRNA expression were reversed by all durations of exercise in Hipp. However, only 2 and 4 weeks, but not 6 weeks, of exercise reduced elevations in PFC and NAc Il-1β expression.

CONCLUSION

Forced exercise for 2 and 4 weeks attenuates TRA-seeking behavior partially through the regulation of Bdnf and Il-1β mRNA expression.

Exploring exercise interventions in substance abuse treatment: A comprehensive bibliometric analysis

This study aims to comprehensively evaluate the research landscape related to exercise and substance abuse over the past 2 decades. A systemic bibliometric analysis was conducted using 2 powerful tools, the Bibliometrix package for R and VOSviewer software. The analysis covered a corpus of literature indexed in the Web of Science's core collection. The publication counts related to exercise interventions within the context of substance abuse from 2004 to 2023, key journals extensively publishing research on this topic, institutional affiliations contributing significantly to this field, frequently co-occurring keywords to highlight research focal areas, and citation patterns for these studies were examined. The analysis identified a total of 2110 articles during the specified period. Notably, there has been a discernible upward trend in publication volume within this field over the past 2 decades. Prominent journals featuring extensive research on this topic include Drug and Alcohol Dependence, Frontiers in Psychiatry, and International Journal of Environmental Research and Public Health. Among the notable contributors to the field are researchers Greer TL and Trivedi MH. The University of California's system has also emerged as a leading institution, fostering collaborations with diverse research entities. The most frequently recurring keywords were exercise, substance abuse, substance use disorders, mental health, and depression, among others, highlighting the research focus. This study offers insights and recommendations for future research in the area of exercise in substance abuse, emphasizing the need to explore physiological mechanisms and psychological comorbidities to optimize exercise as a therapeutic intervention.

Research trends in exercise therapy for the treatment of pain in postmenopausal osteoporosis over the past decade: A bibliometric analysis

BACKGROUND

Postmenopausal osteoporosis (PMOP) is the most common form of primary osteoporosis among women, and the associated pain often drives patients to seek clinical intervention. Numerous studies have highlighted the unique clinical benefits of exercise therapy (ET) in alleviating PMOP-related pain. However, bibliometric analyses examining collaboration, development trends, and research frontiers in the field of ET for PMOP pain remain scarce.

AIM

To explore the research trends in ET for pain treatment in PMOP patients over the past decade.

METHODS

All scholarly works were meticulously sourced from the Science Citation Index-Expanded within the prominent Web of Science Core Collection. Utilizing the capabilities of CiteSpace 6.2.R5, we conducted a thorough analysis of publications, authors, frequently cited scholars, contributing nations, institutions, journals of significant citation, comprehensive references, and pivotal keywords. Additionally, our examination explored keyword cooccurrences, detailed timelines, and periods of heightened citation activity. This comprehensive search, from 2014 through 2023, was completed within a single day, on October 11, 2023.

RESULTS

In total, 2914 articles were ultimately included in the analysis. There was a rapid increase in annual publication output in 2015, followed by stable growth in subsequent years. Boninger, Michael L, is the most prolific author, whereas Ware JE has the most citations. The United States’ global influence is significant, surpassing all other nations. The University of California System and Harvard University are the most influential academic institutions. J Bone Joint Surg Am is the most influential journal in this field. “Spinal cord injury” is the keyword that has garnered the most attention from researchers. The developmental pattern in this field is characterized by interdisciplinary fusion, with different disciplines converging to drive progress.

CONCLUSION

The academic development of the field of ET for pain in PMOP has matured and stabilized. Clinical management and rehabilitation strategies, along with the mechanisms underlying the relationship between ET and bone resorption analgesia, continue to be the current and future focal points of research in this field.

Unlocking the age-old secrets of reward and substance use

Although substance use is widespread across the lifespan from early adolescence to older adulthood, the prevalence of substance use disorder (SUD) differs between age groups. These age differences in SUD rates necessitate an investigation into how age moderates reward sensitivity, and consequently influences the risks and consequences related to substance use. This theoretical review integrates evidence from the literature to address the dynamic interplay between age and reward in the context of substance use. Overall, increasing evidence demonstrates that age moderates reward sensitivity and underlying reward system neurobiology. Reward sensitivity undergoes a non-linear trajectory across the lifespan. Low levels of reward sensitivity are associated with childhood and late adulthood. In contrast, high levels are associated with early to late adolescence, followed by a decline in the twenties. These fluctuations in reward sensitivity across the lifespan contribute to complex associations with substance use. This lends support to adolescence and young adulthood as vulnerable periods for the risk of subsequent SUD. More empirical research is needed to investigate reward sensitivity during SUD maintenance and recovery. Future research should also involve larger sample sizes and encompass a broader range of age groups, including older adults.

Dopamine Pharmacodynamics: New Insights

Dopamine is a key neurotransmitter involved in physiological processes such as motor control, motivation, reward, cognitive function, and maternal and reproductive behaviors. Therefore, dysfunctions of the dopaminergic system are related to a plethora of human diseases. Dopamine, via different circuitries implicated in compulsive behavior, reward, and habit formation, also represents a key player in substance use disorder and the formation and perpetuation of mechanisms leading to addiction. Here, we propose dopamine as a model not only of neurotransmission but also of neuromodulation capable of modifying neuronal architecture. Abuse of substances like methamphetamine, cocaine, and alcohol and their consumption over time can induce changes in neuronal activities. These modifications lead to synaptic plasticity and finally to morphological and functional changes, starting from maladaptive neuro-modulation and ending in neurodegeneration.

Effect of aerobic exercise on brain metabolite profiles in the mouse models of methamphetamine addiction: LC-MS-based metabolomics study

Methamphetamine (MA) abuse is recognized as a brain disorder, and physical activity has clear benefits for MA use disorders. The specific mechanisms by which physical activity alleviates MA use disorders are currently not fully understood. Based on this, the present study used untargeted metabolomics using liquid chromatography-mass spectrometry (LC-MS) to analyze the metabolic changes induced by MA in the brains of mice by exercise intervention. It was found that after 2 weeks of treadmill training, aerobic exercise modulated MA-induced brain metabolic disorders, in which 129 metabolites existed that were significantly differentiated in response to MA induction, and 32 metabolites were significantly affected by exercise. These differential metabolites were mainly enriched in glycerophospholipid metabolism, steroid hormone biosynthesis and degradation, and renin-angiotensin system pathways. To our knowledge, this study is the first to use LC-MS to investigate the effects of aerobic exercise on MA-induced brain metabolic profiling. The findings of this study provide new insights into exercise therapy using MA.

The impact of aerobic exercise training on cognitive function and gut microbiota in methamphetamine-dependent individuals in the community

OBJECTIVE

This study aimed to investigate the impact and mechanism of gut microbiota on the enhancement of cognitive function in methamphetamine (MA)-dependent individuals during aerobic exercise training.

METHODS

A total of sixty-four MA-dependent individuals were randomly assigned to either an aerobic exercise training group (DK, n = 32) or a conventional rehabilitation group (CK, n = 32). After an eight-week intervention, the participants' working memory and inhibition ability were assessed using the Stroop paradigm and Go/NoGo paradigm, respectively. Gut microbiota composition was analyzed using high-throughput sequencing.

RESULTS

1) Eight weeks of aerobic exercise training significantly improved the working memory and inhibition ability of MA-dependent individuals (P < 0.05). 2) Following the intervention, the DK group exhibited significantly higher levels of Lactobacillus, Lactococcus lactis, Prevotellaceae, and Ruminococcaceae compared to the CK group. Conversely, the DK group demonstrated significantly lower levels of Desulfovibrio and Akkermansia compared to the CK group. Furthermore, the DK group showed significantly increased metabolic pathways associated with d-Glutaralate and d-Galactate Degradation, as well as the Alanine, aspartate, and glutamate metabolism pathway, compared to the control group. 3) Cognitive function related to MA addiction positively correlated with Bifidobacterium, Dialister, and Adlercreutzia, while negatively correlated with Enterobacteria, Bacillus cereus, Catabacter, and Akkermansia.

CONCLUSION

Aerobic exercise training enhances working memory and inhibition ability in MA-dependent individuals, thereby mitigating the detrimental effects of MA addiction on cognitive function. Additionally, analysis of gut microbiota suggests that the modulation of gut microbiota and associated metabolic pathways play a role in regulating the improvement of cognitive function in MA-dependent individuals through exercise.

The Role of Physical Exercise in Opioid Substitution Therapy: Mechanisms of Sequential Effects

It is generally accepted that chronic opioid use is associated with structural and functional changes in the human brain that lead to an enhancement of impulsive behavior for immediate satisfaction. Interestingly, in recent years, physical exercise interventions have been used as an adjunctive treatment for patients with opioid use disorders (OUDs). Indeed, exercise has positive effects on both the biological and psychosocial basis of addiction, modifying neural circuits such as the reward, inhibition, and stress systems, and thus causing behavioral changes. This review focuses on the possible mechanisms that contribute to the beneficial effects of exercise on the treatment of OUDs, with emphasis placed on the description of a sequential consolidation of these mechanisms. Exercise is thought to act initially as a factor of internal activation and self-regulation and eventually as a factor of commitment. This approach suggests a sequential (temporal) consolidation of the functions of exercise in favor of gradual disengagement from addiction. Particularly, the sequence in which the exercise-induced mechanisms are consolidated follows the pattern of internal activation-self-regulation-commitment, eventually resulting in stimulation of the endocannabinoid and endogenous opioid systems. Additionally, this is accompanied by modification of molecular and behavioral aspects of opioid addiction. Overall, the neurobiological actions of exercise in combination with certain psychological mechanisms appear to promote its beneficial effects. Given the positive effects of exercise on both physical and mental health, exercise prescription is recommended as a complement to conventional therapy for patients on opioid maintenance treatment.

A red nucleus-VTA glutamate pathway underlies exercise reward and the therapeutic effect of exercise on cocaine use

Physical exercise is rewarding and protective against drug abuse and addiction. However, the neural mechanisms underlying these actions remain unclear. Here, we report that long-term wheel-running produced a more robust increase in c-fos expression in the red nucleus (RN) than in other brain regions. Anatomic and functional assays demonstrated that most RN magnocellular portion (RNm) neurons are glutamatergic. Wheel-running activates a subset of RNm glutamate neurons that project to ventral tegmental area (VTA) dopamine neurons. Optogenetic stimulation of this pathway was rewarding, as assessed by intracranial self-stimulation and conditioned place preference, whereas optical inhibition blocked wheel-running behavior. Running wheel access decreased cocaine self-administration and cocaine seeking during extinction. Last, optogenetic stimulation of the RNm-to-VTA glutamate pathway inhibited responding to cocaine. Together, these findings indicate that physical exercise activates a specific RNm-to-VTA glutamatergic pathway, producing exercise reward and reducing cocaine intake.

Exercise Regulates the Metabolic Homeostasis of Methamphetamine Dependence

Physical exercise is effective in enhancing cognitive function, reducing anxiety and depressive symptoms, reducing cravings, and improving quality of life in methamphetamine (METH) addiction. However, little is known about the effect of exercise on metabolic profiles. We performed LC/MS-based targeted metabolic profiling on serum samples to investigate the metabolic characteristics of METH dependence and find the differences between METH-dependent individuals and nonusers and evaluated the metabolomic profiles of individuals with METH dependence following aerobic exercise training. We identified a total of 201 metabolites, among which 115 were differentially expressed under METH use. Among the differentially regulated metabolites, 72 were selected as potential biomarkers. Further analysis identified 19 pathways, among which glyoxylate and dicarboxylate metabolism; alanine, aspartate, and glutamate metabolism; and citrate cycle were most significantly affected by METH. The aerobic exercise intervention differentially regulated 55 metabolites, of which 51 were selected as potential biomarkers and were mainly enriched in 10 pathways. Interestingly, alanine, aspartate, and glutamate metabolism and nitrogen metabolism were the remarkably affected pathways. Furthermore, METH increased the serum levels of glutamate and decreased GABA, whereas exercise decreased the serum levels of glutamate and increased GABA. Results suggested that METH dependency disturbed normal metabolic homeostasis, whereas exercise restored metabolism.

Overcoming reward deficiency syndrome by the induction of “dopamine homeostasis” instead of opioids for addiction: illusion or reality?

Many individuals in the United States are plagued by addiction, and the rate at which it is affecting people in the United States only seems to be increasing. Research shows that addiction is a preventable disorder rather than a flaw in one’s moral fiber. It is driven by the imbalance of dopamine and the brain’s reward system. Although medication-assisted treatment (MAT), the most common treatment for addiction, are effective in reducing harm, they provide minimal aid in addressing the root cause of this preventable disorder. The authors aim to convey that the proper treatment should help restore dopamine balance so the quality of life can be improved in the recovering community. Osteopathic principles emphasize the importance of homeostasis and allostasis in allowing the body to heal itself. Viewing reward deficiency syndrome (RDS) through this osteopathic lens can bring about treatments that aim to restore the dopamine homeostasis. The article discusses various potential therapeutic modalities that can provide dopamine homeostasis via activation of dopaminergic pathways.

Dopaminergic and glutamatergic biomarkers disruption in addiction and regulation by exercise: a mini review

INTRODUCTION

Drug addiction is associated with disruption of a multitude of biomarkers in various brain regions, particularly in the reward center. The most pronounced are dopaminergic and glutamatergic biomarkers, which are affected at various levels. Neuropathological changes in biomarkers alter the homeostasis of the glutamatergic and dopaminergic nervous systems and promote addiction-associated characteristics such as repeated intake, maintenance, withdrawal, reinstatement, and relapse. Exercise has been shown to have a buffering effect on such biomarkers and reverse the effects of addictive substances.

METHODS

A review of the literature searched in PubMed, examining drug addiction and physical exercise in relation to dopaminergic and glutamatergic systems at any of the three biomarker levels (i.e., neurotransmitter, receptor, or transporter).

RESULTS

We review the collective impact of addictive substances on the dopaminergic and glutamatergic systems and the beneficial effect of exercise in terms of reversing the damage to these systems. We propose future directions, including implications of exercise as an add-on therapy, substance use disorder (SUD) prognosis and diagnosis and designing of optimized exercise and pharmaceutical regimens based on the aforementioned biomarkers.

CONCLUSION

Exercise is beneficial for all types of drug addiction at all stages, by reversing molecular damages caused to dopaminergic and glutamatergic systems.

Exercise can restore behavioural and molecular changes of intergenerational morphine effects

In our previous studies, the offspring of morphine-exposed parents (MEO) showed pharmacological tolerance to the morphine's reinforcing effect. According to the role of exercise in treatment of morphine addiction, the current study was designed to utilize exercise to improve the effect of parental morphine exposure on the morphine's reinforcing effect. Male and female rats received morphine for 10 days and were drug-free for another 10 days. Each morphine-exposed animal was allowed to mate either with a drug-naïve or a morphine-exposed rat. The offspring were divided into two groups: (1) offspring that were subjected to treadmill exercise and (2) offspring that were not subjected to exercise. The reinforcing effect of morphine was evaluated using conditioned place preference (CPP) and two-bottle choice (TBC) tests. Levels of dopamine receptors (D1DR and D2DR), μ-opioid receptor (MOR), and ΔFosB were evaluated in the nucleus accumbens. The MEO obtained lower preference scores in CPP and consumed morphine more than the control group in TBC. After 3 weeks of exercise, the reinforcing effect of morphine in the MEO was similar to the control. D1DR, D2DR, and MOR were increased in MEO compared with the controls before exercise. Levels of D1DR and MOR were decreased after exercise in the MEO; however, D1DR was increased in control. D2DR level did not change after exercise in MEO, but it increased in control group. Moreover, the level of ΔFosB was decreased among MEO while it was increased after exercise. In conclusion, exercise might modulate the reinforcing effect of morphine via alteration in levels of D1DR, MOR, and ΔFosB.

Effects of moderate-intensity exercise on social health and physical and mental health of methamphetamine-dependent individuals: A randomized controlled trial

OBJECTIVE

Methamphetamine (MA)-dependent individuals' health problems are widespread and need to be solved urgently. Exercise is considered a potential treatment for MA dependents. The study aimed to determine the effects of a 12-week aerobic exercise on the social, physical, and mental health of MA-dependent individuals.

MATERIALS AND METHODS

Sixty MA-dependent individuals were randomly assigned into two groups. Subjects in the exercise group (n = 30) received an exercise intervention five days a week for 60 min each for 12 weeks. Subjects in the control group (n = 30) received regular corrective rehabilitation without exercise in the same setting. Outcome measures, including questionnaires [quality of life scale for drug addiction (QOL-DA), self-rating anxiety scale (SAS), self-rating depression scale (SDS), and Pittsburgh sleep quality index (PSQI)] and physical fitness, were arranged the day before the start of the intervention and the day after the end of the intervention. Two-factor repeated measures ANOVA was used to compare the treatment differences between the two groups.

RESULTS

After 12 weeks of the intervention period, social health was significantly improved in the exercise group (P < 0.01), and there was a statistically significant difference in mental health scores between exercise group and control group, with a greater impact in exercise group.(Psychology: P < 0.01; SAS: P < 0.01; SDS: P < 0.01; PSQI: P < 0.01), physical health improved in the exercise group, physiology (P < 0.01), symptom (P < 0.01), heart rate (P < 0.01), systolic blood pressure (P < 0.01), systolic blood pressure (P < 0.01), vital capacity (P < 0.05), grip (P < 0.01), vertical jump (P < 0.001), sit and reach (P < 0.01), 50-meter run (P < 0.01), and reaction time (P < 0.01).

CONCLUSION

Aerobic exercise intervention is an effective treatment for MA-dependent individuals, and the 12-week intervention improved the social, physical, and mental health of MA-dependent individuals. We recommend that future studies focus more on drug-dependent individuals' overall health status rather than just relapse.Clinical trial registration: [https://www.chictr.org.cn/hvshowproject.aspx?id=131048], identifier [ChiCTR2200055348].